Radio frequency identification (RFID) is a well known technology that has been utilized in many different industries, i.e., the shipping industry to track packages, the retail industry to prevent thefts, etc. RFID technology uses electromagnetic energy as a medium for transmitting information between an RFID reader and a type of a circuit referred to as an RFID tag. In general, the RFID reader can detect and read data, i.e., a tag identifier (tag ID), that is stored within the RFID tag.
RFID tags can be either passive or active. Passive tags do not have a separate power source and often use modulated backscatter to reflect energy back to the RFID reader. Other types of passive tags may discharge a capacitor that was charged using the RF energy from the RFID reader's interrogation signal, or ping. Active tags, on the other hand, have power sources that enable the tag to send data back to the reader. Active RFID tags typically can send data over a larger range than their passive RFID counterparts. Both varieties of RFID tags provide for non-contact and non-line of sight sensing.
When an RFID reader reads or detects an RFID tag, the RFID reader emits an RF signal. RFID tags within the RF field respond by transmitting the tag ID to the RFID reader. The RFID reader can provide the tag ID to one or more different computer systems that are coupled to the RFID reader. The computer systems can implement various processes based upon the tag ID received.